This activity was first developed at the laboratories of Glasgow Scientific Services. SSERC became involved via a collaboration with the Scottish Food and Drink Federation.
From a chemistry point of view, the activity uses the context of food colourings as the context for work on chromatography.
The extraction is the novel part: it uses Solid Phase Extraction (SPE) cartridges to extract the colouring from soft drinks which can then be eluted with a smaller volume of a different solvent, thus being concentrated enough for analysis by paper chromatography or TLC.
Colour extraction (Pupil)
Colour extraction (Teacher / Technician)
Chromatography (Teacher / Technician)
Colour extraction risk assessment
Discussion activity on food additives